Madison Sporting Goods via eBay offers the Mongoose Men's 26" Dual Suspension Mountain Bike in Matte Grey for $149.99 with free shipping. That's $30 off list and the lowest price we could find, although we saw it in January for $20 less. It features a full suspension steel frame, suspension fork, 21-speed shifter, Shimano rear derailleur, 3-piece crank, front disc brakes, and rear linear pull brakes.

Update: The price has dropped to $134.99.